My phone is not able to make or receive calls, why?
Despite being connected to the network, I am unable to make calls or receive calls on my iPhone 4.
When I try to make a call, the phone immediately shows "call failed" even without any ringing.
When others call my number, they report that my phone is 'disconnected.'
I am able to send and receive SMS messages, but no calls. What is wrong? How can I correct this? I am lost without the use of my phone.
Is this a good question?